The storage service of Waylay is a utility service that lets you store and retrieve any file as a storage object in one of the four predefined buckets.
Each modification (upload, delete) can be configured to trigger a specific waylay webscript. A notification subscription on the storage service defines such a notification rule.
Waylay provides predefined storage buckets that each have their specific purpose:
assets is a general bucket where you can put images, documents,… that require authenticated access. See the object signing API on how to retrieve a signed link to the file content with limited time validity.
If enabled, the ETL export Service will write export files to the readonly etl-export bucket.
Files placed in the
upload/ folder of the etl-import bucket will initiate a timeseries import process.
See ETL Import Service for more details.
For any object placed into this public bucket, a readonly link is made available that is accessible to anyone without authentication.
This can be used to store or publish assets (images, text files) that you might need to be publicly available in your waylay solution.
Depending on the access policies, any file in a bucket can be downloaded, deleted, or referenced by a shareable link.
A notification subscription is a rule, associated with a storage bucket, that defines:
- a target webscript that can be triggered by a change in the bucket
- one or more event filters that state
- the event type (file change and/or file delete)
- optionally a required prefix or suffix for the file name
If a change or deletion in a bucket matches any event filter in any of its subscriptions, the corresponding webscript will be invoked, with a payload message that contains a reference to the changed file.
This can be a powerful integration tool to, by example,
- automate the creation of waylay resources based on a definition file through a simple upload
- convert a file upload to waylay message that triggers a rule
See the Storage REST API for more details on this integration.
To list the subscriptions that are active on a bucket, use the subscription action on the bucket in the root bucket listing view.
The list view lets you define new subscriptions, or inspect existing ones using the subscription editor.
the subscription editor
All buckets, except etl_import support notification subscriptions.
The subscription listing for the etl_import bucket contains a single, non-modifiable system subscription that handles the ETL Import process.